Method of manufacturing semiconductor light emitting device

Abstract

A method of manufacturing a semiconductor light emitting device comprises the steps of: forming a p-InP first semiconductor layer (11) on a p-type semiconductor substrate (10) by a first growth or diffusion; forming a groove (15) shaped like a stripe in the substrate and the first semiconductor layer; and successively forming a p-InP second semiconductor layer (12), a p or n-InGaAsP third semiconductor layer (13) and an n-InP fourth semiconductor layer (14) in the regions including the inner and outer portions of the grooves by the second growth. In this manufacturing method, the carrier concentration of the p-type impurity in the first semiconductor layer is selected to be higher than the carrier concentration in the fourth semiconductor layer. As a result, by the growth process of the respective semiconductor layers in the inner and outer portions of the groove or by the heat treatment after a growth process, the impurity can be diffused from the first semiconductor layer into the fourth semiconductor layer and the p-n junction faces can be moved from the inner surfaces of the groove into the fourth semiconductor layer.

What is claimed is: 
     
       1. A method of manufacturing a semiconductor light emitting device wherein an exposed surface and a p-n junction displaced therefrom are in a non-intersecting relationship comprising the steps of: providing a semiconductor substrate (10, 11) having a surface layer of a first conductivity type,   forming a stripe shaped groove (15) in said semiconductor substrate of said first conductivity type,   forming successively a first semiconductor layer (12) of said first conductivity type and a second semiconductor layer (13) of either conductivity type in regions including the inner portion of said groove, and then forming a third semiconductor layer (14) of said second conductivity type on said second semiconductor layer and in regions inside and outside said groove, said third semiconductor layer being directly grown on said surface layer of the substrate and forming a p-n junction interface therein, and   diffusing the impurity of said first conductivity type from said surface layer of the semiconductor substrate into said third semiconductor layer by the growth process of the respective semiconductor layers inside and outside said groove, so that the p-n junction interface moves from the inner surfaces of said groove and said surface layer into said third semiconductor layer.   
     
     
       2. A method of manufacturing a semiconductor light emitting device in accordance with claim 1, wherein the impurity of said first conductive type is Zn.   
     
     
       3. A method of manufacturing a semiconductor light emitting device in accordance with claim 1, wherein said step of providing a semiconductor substrate having a surface layer comprises the step of duffusing an impurity of said first conductivity type.   
     
     
       4. A method of manufacturing a semiconductor light emitting device in accordance with claim 1, comprising the further step of forming an underlayer of said surface layer of the substrate of said second conductivity type. 
     
     
       5. A method of manufacturing a semiconductor light emitting device in accordance with claim 1, wherein said step of forming the second semiconductor layer comprises forming said second semiconductor layer of InGaAsP and the steps of forming the other semiconductor layers comprises forming said layers of 
     
     
       6. A method of manufacturing a semiconductor light emitting device wherein a grooved surface and a p-n junction displaced therefrom are in a non-intersecting relationship comprising the steps of: providing a semiconductor substrate of a first conductivity type,   forming a stripe shaped groove (15) in said semiconductor substrate of said first conductivity type,   forming successively a first semiconductor layer (12) of said first conductivity type and a second semiconductor layer (13) of either conductivity type in regions including the inner portion of said groove, and then forming a third semiconductor layer (14) of said second conductivity type on said second semiconductor layer and in regions inside and outside said groove, said third semiconductor layer being directly grown on said substrate and forming a p-n junction interface therein, and   diffusing the impurity of said first conductivity type from said semiconductor substrate into said third semiconductor layer by the growth process of the respective semiconductor layers inside and outside said groove so that the p-n junction interface moves from the inner surfaces of said groove and said surface layer into said third semiconductor layer.   
     
     
       7. A method of manufacturing a semiconductor light emitting device wherein a grooved surface and a p-n junction displaced therefrom are in a non-intersecting relationship comprising the steps of: providing a semiconductor substrate (10, 11) having a surface layer of a first conductivity type,   forming a stripe shaped groove (15) in said semiconductor substrate of said first conductivity type,   forming successively a first semiconductor layer (12) of said first conductivity type and a second semiconductor layer (13) of either conductivity type in regions including the inner portion of said groove, and then forming a third semiconductor layer (14) of said second conductivity type on said second semiconductor layer and in regions inside and outside said groove, said third semiconductor layer being directly grown on said surface layer of the substrate and forming a p-n junction interface therein, and   diffusing the impurity of said first conductivity type from said surface layer of the semiconductor substrate into said third semiconductor layer by a heat treatment after the growth process of the respective semiconductor layers inside and outside said groove so that the p-n junction interface moves from the inner surfaces of said groove and said surface layer into said third semiconductor layer.   
     
     
       8. A method of manufacturing a semiconductor light emitting device wherein an exposed surface and a p-n junction displaced therefrom are in a non-intersecting relationship comprising the steps of: providing a semiconductor substrate (10, 11) having a surface layer of a first conductivity type,   forming a stripe shaped groove (15) in said semiconductor substrate of said first conductivity type,   forming successively a first semiconductor layer (12) of said first conductivity type and a second semiconductor layer (13) of either conductivity type in regions including the inner portion of said groove and then forming a third semiconductor layer (14) of said second conductivity type on said second semiconductor layer and in regions inside and outside said groove, said third semiconductor layer being directly grown on said surface layer of the substrate and forming a p-n junction interface therein, and   providing in said third semiconductor layer a concave interface with said substrate p-n-junction inside and outside the groove for diffusing the impurity of said first conductivity type from the side of the interface, inside and outside the groove, substrate into said third semiconductor layer so that p-n junction interfaces are moved by a heating process from the inner surfaces of said groove and from surfaces outside said groove to form said concave p-n junction in said third semiconductor layer.